Although, I'm not sure about the entirety of this question, when reviewing claims and evidence, check your sources to make sure they are reliable.
I think its C. global warming
because the other one directly threats aquatic bio diversity while global warming doesn't just affect aquatic biodiversity
I believe it's B. synthesizing new DNA from RNA sequences.
Answer:B.The signal is either similar in structure to a ligand used by eukaryotes, or this signaling pathway is utilized by both prokaryotes and eukaryotes.
Explanation: Eucaryotic cell is a cell whose Nucleus is clearly defined and confined within a membrane.
Procaryotic cell is a cell which does not have a clearly defined Nucleus.
Signals are stimuli which can be felt by an organism, specific organismal have its own kinds of signals which it can respond to,but some times signals with specific features can create response in two or more type or species of organisms. What happened in the lab is a case where a partial signal can be sensed by both procaryotes and eucaryotes because it has either a similar structure or its pathway can be used by either Eucaryotic cells and procaryotic cells.
